Insulated flue pipe



Ap 14, 1953 R. F. TWICKLER 2,634,759

INSULATED FLUE PIPE Filed July 27, 1949 3nventor flwymana/Z't 71v icil Gttorn J Patented Apr. 14, 1953 UNITED STATES PATENT OFFICE INSULATED FLUE PIPE Application July 27, 1949, Serial No. 107,062

1 Claim. 1

The invention relates to insulated flue pipes, and has for its object to provide a device of this kind comprising inner and outer pipes in spaced relation, and formed from sheet metal, and spacing members carried by the inner and outer pipes and secured together in the space between the pipe walls.

A further object is to provide spacing means between the inner and outer pipes within the air space around the inner pipe and comprising struck-in lugs carried by the outer pipe and struck-out lugs carried by the inner pipe, the lugs of the pipes registering and engaging and secured together, preferably by welding, thereby forming a rigid insulated pipe.

A further object is to provide a flue pipe comprising inner and outer pipes having an air space around the inner pipe and spacing lugs carried by the pipes.

With the above and other objects in view the invention resides in the combination and arrangement of parts as hereinafter set forth, shown in the drawing, described and claimed, it being understood that changes in the precise embodiment of the invention may be made within the scope of what is claimed without departing from the spirit of the invention.

In the drawing:

Figure l is a perspective view of the pipe, showing a section therethrough.

Figure 2 is a vertical longitudinal sectional view through the form of flue pipe shown in Figure 1.

Figure 3 is a vertical transverse sectional view through a round form of pipe.

Figure 4 is a view similar to Figure 3 showing an 01f round form of flue pipe.

Referring to the drawing, the numeral l designates the outer pipe and 2 the inner pipe, whichpipes are in spaced relation thereby forming an inner insulating chamber 3 entirely around the inner pipe 2.

Struck-in from the walls of the outer pipe 2 are frusto conically shaped lugs 4 longitudinally spaced as well as circumferentially spaced. Struck-in lugs 4 register with struck-out lugs 5, which are also frusto conically shaped and which are struck-out from the inner pipe 2. By forming the lugs frusto conically shaped relatively wide engaging surfaces 6 are formed, and which surfaces are secured together in any suitable manner, however preferably welded at I, therefore it will be seen that a rigid insulated flue is formed, and one which can be easily and quickly, assembled. At the same time the chamber 3 Will form an insulating space or a ventilating space, if desired.

It will be seen that the inner pipe 2 can be easily and quickly assembled as the lugs 4 and 5 are preformed in exact position, and the lugs can be connected together by spot welding. Although the device is shown in the form of a straight flue, it is obvious elbows and other pipe forms may be made, and the usual J'oints may be placed on the ends of the elements formed in accordance with the invention.

From the above it will be seen that an insulat ed flue is provided which is simple in construction and one which may be easily and cheaply manufactured and sold. It will also be seen that it will only be necessary, in assembling, to place one pipe within the other with the lugs in registry and then to weld or secure the lugs together.

The invention having been set forth what is claimed as new and useful is:

An insulated flue comprising an outer pipe, an inner pipe within the outer pipe in spaced relation thereto thereby forming a chamber around the inner pipe, said inner pipe having struck-out frusto conically shaped lugs extending half way across the chamber, the outer pipe having struckin frusto conically shaped lugs in registry with and engaging the outer ends of the struck-out frusto conically shaped lugs of the inner pipe, means securing the adjacent faces of said frusto conically shaped lugs together, the engaging ends of said frusto conically shaped lugs being of the same area.

RAYMOND FRANCIS TWICKLER.

References Cited in the flle of this patent UNITED STATES PATENTS Number Name Date 531,000 Morrison Dec. 18, 1894 1,150,407 Wells Aug. 17, 1915 1,930,285 Robinson Oct. 10, 1933 1,930,782 Turner Oct. 17, 1933 FOREIGN PATENTS Number Country Date 309,646 Germany Mar. 17, 19 17 

